Facebook expected that less than one per cent of the fan count on corporate pages would be reduced as a result of the crackdown.
“Newly improved automated efforts will remove those Likes gained by malware, compromised accounts, deceived users, or purchased bulk Likes,” Facebook said in a post on its official blog on Friday.
“While we have always had dedicated protections against each of these threats on Facebook, these improved systems have been specifically configured to identify and take action against suspicious Likes,” the post continued.
Purchasing such Likes is forbidden by Facebook but due to a growing black market many companies use the practice to raise their profile.
Many of these Likes come from bogus Facebook user accounts rather than genuine users of the social network.
Meanwhile, various spam-like programs on Facebook deceive users into unwittingly liking something when they perform another action, such as clicking to watch a video, Reuters reported.
Facebook said the cleanup will benefit both users and companies that maintain pages on the network, by giving a more accurate measurement of fan count and demographics.
“It’s their currency,” said Jeremiah Owyang, a partner at research firm Altimeter Group. “Facebook is playing the Federal Reserve, to take the counterfeit currency off the market to ensure that there’s quality in the marketplace.”
The problem is not unique to Facebook, say analysts, who note that Twitter and Google also grapple with fake accounts, spam and other techniques to game the service.